Singapore: Wilkinson Eyre completes new addition to Gardens by the Bay

Located in Marina Bay, Gardens by the Bay is a key project in delivering the Singapore Government’s vision of transforming Singapore into a ‘City in a Garden’. The commission to design the 54 hectare Bay South Garden was won in 2006 by a team led by Grant Associates and including Wilkinson Eyre Architects, Atelier One, and Atelier Ten. At the heart of Bay South Garden is the Cooled Conservatory Complex.

The two Conservatories, designed by Wilkinson Eyre Architects, cover an area in excess of 20,000 sq m and are among the largest climate controlled glasshouses in the world. They provide a spectacular, all-weather attraction and comprise a 1.28 hectare cool dry conservatory (the ‘Flower Dome’) and a 0.73 hectare cool moist conservatory (the ‘Cloud Forest’). Each has its own distinct character, but both explore the horticulture of those environments most likely to be affected by climate change.

The Cooled Conservatories are designed with as much environmental control as possible achieved through passive means before resorting to highly efficient, active systems. The principal design challenge of the biomes is the conflicting need to maintain the high light levels required by the plants whilst minimising the associated solar heat gain. The form of the biomes are optimised environmentally by containing a large volume within a relatively small surface area. In addition, the form of the Flower Dome is tilted forward so that it leans over towards the Marina Bay; the north façade is therefore self-shaded and never receives the full glare of the sun.

The envelope is critical to the success of the system: the structure has been designed to cast as little shadow as possible whilst highly selective glass is used to filter out as much heat as possible. The glazing has very high visual light transmission coupled with a very low solar heat gain coefficient. This is achieved through a low e coating on Face #2 of the glass, which means that approximately 64% of light is transmitted into the building with only 38% of the corresponding solar heat gain. When the sun comes out, deployable shades are used to control the light levels and limit the heat gain.

Inside, cool air is delivered at low velocity, trickling in and between the planted displays, providing the right growing conditions for the plants as well as comfort for the visitors. The fresh air is drawn in and dried with desiccant prior to passing through conventional chillers, reducing the amount of energy required for cooling; hot air collected from the top of the glasshouses is used to regenerate the desiccant by driving off the moisture. The on-site biomass boiler is fueled entirely with green waste from the city’s parks.

The project has been accredited BCA Green Mark Platinum (the highest grade in the BCA Green Mark environmental assessment system).